The invention relates to a vehicle drive line between two driven axles of a four wheel drive vehicle or the like. More specifically, the present invention relates to an improved design of a planetary transmission connecting the drive for the two driven axles.
In U.S. Patent Texts Nos. 4,464,973 and 4,520,691, planetary transmissions are described that have an input shaft and a first sun gear as well as a second sun gear that has an output shaft. The sun gears interact with planet gears that are provided at a planet carrier. However, the mounting of the input shaft and of the output shaft does not meet specifically defined power transmission requirements of a drive line, particularly those of a passenger car equipped with an all-wheel drive.
DE-PS 3 507 490 shows a planetary transmission having a centrifugal brake that is connected into the drive line of a passenger car equipped with an all-wheel drive, this drive line connecting two driven axles.
It is an object of the invention to design the components, specifically the input shaft and the output shaft of the planetary transmission connected into a drive line, in such a way that, while they can be manufactured cost-effectively and are easy to mount, they absorb and transmit the occurring forces as well as torques in an operationally appropriate way.
This objective is achieved by providing a housing, an input shaft projecting into the housing and having an open bore, and an output shaft having an end projecting into the open bore of the input shaft and supported by a supporting plate which closes the housing.
The main advantages that are achieved by means of the invention are that the input shaft and the output shaft are disposed and integrated into the planetary transmission or its housing in such a way that the occurring forces and torques in the drive train are transmitted without any problem. The mounting of both shafts and also of the parts of the planetary transmission is simple, particularly because of the bearing insert of the supporting plate and the fixing of the input shaft at the two tapered roller bearings. The components that are arranged in the housing can be manufactured in a simple way.
In preferred embodiments where the planetary transmission is equipped with a centrifugal brake and is integrated into the drive line of a passenger car equipped with an all-wheel drive, the housing that houses the planetary transmission and the centrifugal brake is shaped advantageously with respect to space in that the brake shoes of the centrifugal brake are provided between the sun gears of the planetary transmission and the housing. The light-metal alloy housing that has a circular-cylindrical cross-section, for absorbing the frictional forces, on the interior side, has a surrounding iron-metallic ring. This ring may be cast together with the housing as an insert or may be fastened at the latter by form or friction fitting.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.